Preparation of chlorhydrins and polyhydric alcohols from olefins



Patented June 12, 1945 PREPARATION I OF CHLOBHYDRINS AND POLYHYDRICALCOHOLS FROM OLEFINS Cortes F, Reed, Anoka, Minn., asslgnor to CharlesL. Horn, Minneapolis, Minn.

No Drawing. Application December 20, 1938, Serial No. 246,901

6 Claims.

The present invention relates to new methods ofreacting gaseoushydrocarbons with halogens and the oxides of sulphur, selenium ortellurium and to new and useful products and intermediate productsresulting therefrom.

. I have discovered that when an alkene, such as ethylene or propyleneis mixed with a halogen such as chlorine and one of the aforementionedoxides, for example sulphur dioxide, that a reaction takes place, and asa result valuable products are produced.

I have discovered further that when a mixture of an oxide of sulphur,tellurium or selenium, a halogen and a gaseous hydrocarbon, for example,ethyene r propylene are passedinto a strong acid such as sulphuricorphosphoric, a

reaction takes place and a valuable products are produced. When usingethylene as the gaseous hydrocarbon along with chlorine and sulphurdioxide in the acid method ethylene chlorhydrin and ethylene glycol mayreadily be obtained, and when using propylene, propylene chlorohydrin orglycerine maybe obtained.

It is, therefore, a further object of the present invention to providenew methods of producing products from gaseous hydrocarbons, andspecifically a new method of reacting upon hydrocaricons with halogensand oxides of the group consisting of sulphur, tellurium and selenium inthe presence of an acid.

It is a further object of the invention to provide new methods or makingethylene and propylene chlorhydrin, ethylene glycol and glycerine from,or through the use of ethylene or propylene with sulphur dioxide,chlorine and a strong polybasic mineral acid, such as sulphuric orphosphoric acid.

It is a specific object of the invention to provide a process in whichethylene, sulphur dioxide and chlorine are reacted with, and/orassociated with acid to cause the production of intermediates which arecapable of ready'conversion into ethylene chlorhydrin and ethyleneglycol.

It is another specific object of the invention to provide aprocess inwhich propylene, sulphur dioxide and chlorine are reacted with, and/orassociated with acidto cause the production of intermediates which arecapable of ready conversion into propylene glycol and glycerine.

It is a further object of the invention to provide a processof-recovering the sulphuric acid and by-products of theforegoingprocesses for reuse in such processes. It is a further object of theinvention to provide a. recyclic procedure for reacting uponhydrocarbons. Specifically it is an object to provide a recycllcprocedure for producing ethylene glycol from ethylene, sulphur dioxide,chlorine and sulphuric acid, wherein excess of materials or residualproducts may be purified and/or concentrated and reused in subsequentcycles of the production.

It is also an object to provide a procedure wherein a gaseoushydrocarbon, sulphur dioxide and chlorine is passed through sulphuricacid and the excess passed over to a second and successively tosubsequent vessels containing sulphuric acid.

Other and further objects and advantages of the invention are thoseinherent in the invention hereinafter described, illustrated andclaimed.

In carrying out the present invention, I bring together in a reactionvessel the hydrocarbon gas chosen to be reacted upon, the halogen and anoxide of the group consisting of sulphur, tellurium and selenium. Iprefer to utilize chlorine as the halogen and sulphur dioxide as theoxide. Furthermore these reactants are cheap, readily available andnormally gaseous at the reaction temperatures.

When the three reactants, namely, the hydrocarbon, the halogen and theoxide are brought together a reaction ensues and a desirable productproduced which varies according to the conditions of the reaction.

The reaction may be carried out over a fairly wide temperature range.Temperatures from 0 C. to 100 C. represent a, practical range, but Iprefer that the temperature be maintained at about 30 to C. Thetemperature used should be insufficient to cause substantialdecomposition of the reaction products or reactants.

A wide ratio of ingredients may be used, thus for each volume of halogenvapor I may use from one-half to five volumes of gaseous hydrocarbon andfrom. one to two volumes sulphur dioxide vapor. Where the halogen oroxide is used in other than the gaseous phase, equivalent weight 14%after 16% invention, a gaseous hydrocarbon, a halogen such as chlorineand sulphur dioxide, or the oxide of tellurium or selenium are passedinto a concentrated polybasic mineral acid, e. g. sulphuric orphosphoric acid. In general in the acid procedure a hydrocarbon such .asethylene, an oxide such as sulphur dioxide, and a halogen such aschlorine'are simultaneously introduced into a body of concentratedsulphuric or-phosphoric acid, wherein a reaction takes place with slightevolution of heat. A wide range of ratios of the three reagents may beused. Thus, for each volume of chlorine or other halogen from one-halfto five volumes or sulphur or other oxide and from one to two volumes ofthe gaseous hydrocarbon may be used. The sulphur dioxide and chlorinemay be preliminarily mixed and then introduced into the acid along withthe ethylene, or the three gases may be introduced concurrently andadmixed in the acid by agitation of the latter. For best results it ispreferable to agitate the acid medium with, for example, a high speedmechanical stirrer, so as to bring about a line dispersion of themixture of gases in the acid. Although not strictly essential, thistreatment prevents the development of local heating and brings aboutbest results.

The acid concentration may vary from 93 to 100%, or fuming sulphuricacid (oleum) may be employed. Preferably an acid of a high concentrationsuch as 95% strength sulphuric acid is used. While phosphoric-acid maybe used, sulphuric acid is preferred- A further advantage is its lowcost.

The mechanics of the reaction in acid are not clearly understood. Theacid medium either absorbs, carries, or becomes one of the products of.

reaction of the constituents and gains weight as the reaction proceeds.Thus in a typical run, there is a gain in weight of about 1.6% after 1%hours; 3V2% after 3 hours: 6% after 6% hours;

ing acid and each provided with an agitator, with such apparatus thethree gases are introduced into the first vessel in quantitiessufllcient that there willbe an excess of gases which are not absorbed.These are conducted to the second and the excess from the second, ifany, to a third reaction vessel, etc. According to this method the freshconcentrated acid is introduced into the third or last vessel of theseries and the charge of acid in each vessel is moved to the nextearlier in the series as the treatment proceeds, thus to cause a, how ofacid through the treating vesselswhich is counter to the flow of thethree gases as reagents.

After the acid has been treated with the oxide halogen and hydrocarbon,to increase its weight.

' the acid mixture is heated to a temperature which is preferably notmore than 150 0., tor about 10 to 15 minutes, preferably under reducedpressure. The length of time during which the heating is continueddepends in part upon the temperature at which the gas treatment of theacid was carried out, but little heating being required when an elevatedtemperature has been maintained during the gas treatment. The effect ofthe afterheatlng of the gas treated acid is probably to cause amolecular rearrangement to take place in the compounds existing in or incombination with the acid.

During the after-"heating sulphur dioxide is evolved where it is used.as one or the reagents.

40 not to be considered as limitingthe inventionJf 1 1 7.4% after 8%hours; 9.6% after 11% hours and hours, or an average gain of .8596 perhour. a

Some of the products of the reaction are soluble in or form combinationswiththe acid, and maybe recovered in usable form as pointed out below.In addition, under certain operating conditions an oily layer forms andseparates as a layer on the treated acid. This oily layer, which isprincipally-chlorinated products, is removed by any desired separatoryprocedure.

The formation of the oily layer of chlorinated products may bemaintained at aminimum or altogether prevented by suitably regulatingthe ratio of oxide to halogen. as for example, by regulating the ratioof sulphur dioxide to chlorine where these are used. Thus by using abouttwo volumes of sulphur dioxide, one volume of chlorine and one volume ofethylene gas, substantially no oily layer is produced. A decrease in thequantity of hydrocarbon oroxide, as compared with the halogen, favorsthe production of the oily layer. 7

The treatment of the acid with the three reagents may take place in onevessel which is suflL This is preferably collected and usedin the'treatmentof additional acid.

The examples given below are illustrative oi the manner of carrying outthe The examples illustrate the may be reacted upon, details of theproceduree.

present invention.

and the compositions thereby produced but 'itls to be clearly understoodthat thefexamples hre i'izample I A five hundred gram mass or? st amDhuric acid having a temperature o1v 25 c wg quickly heated to '50 C.,and-.thereafter-maintained at about 50 c.- -Ethlyene sulpliurdioxide andchlorine were introduced into acid slowly bubbling the gases into theacid which was maintained in a state of agitation'by a rapidly dr'ivenmechanical stirren.

or the gases in the liquid. .The three gases1=were This treatment wascontinued"! f eight hours during which; time'the,

a total of 72 grams weight or about 9-:

hour. Theproducts formed during'the reaction remained soluble except atthe lastQpartof the treatment, at which time an oily layerof'chlorlnated products began to separate out;

The treated acid was then placed p' fl vtory funnel and the oily layerconstituent, which amounted to 48 cc., was separated, out.

. A 300 cc. portion of the treated acid'from which the oilylayer portionhad been removed wasthen ciently largeto absorb and/or react with therediluted with 250 cc. of distilled waterand heated under a refluxcondenser for about thirty minutes. The diluted and heat treated acidwasthen distilled and a cc. fraction collected at from 102 to 106 C. Thisfraction was a mixture of ethylene chlorhydrin and water. gravity of1.083. i Y The 100 cc. fraction ethylene chlorhydrin and water was thenneutralized and refluxed with 30- hydroc'a o s that The agitation acidwas suflicient to maintain a fine It had a specific as'rehos Igramsoieodaashtorthreehours. Therefluxed mass was then concentratedunder twenty inches of mercury vacuum to remove water, and the reelduetaken up with methyl alcohol. Alter evaporation oi the alcohol, 25 cc.of ethylene glycol retion or the treated acid was then heated tors fewminutes under a vacuum or about 25" to draw Ofl residual chlorine andsulphur dlolld,

and then heated under reflux after dilution with 300 cc; of water. Themasswas then distilled and a 200 cc. traction collected between boilingtemperatures of 102 and 105 C. This fraction was a slightly acid mixtureof ethylene chlor hydrin and water.

The ethylene chlorhydrin solution was neutral- .ized with sodiumhydroxide and saponitled orhydrolyzed with sodium carbonate, thenconcentrated by evaporation under reduced pressure.

The residue which contained ethylene glycol and i a tilled. The oilyproduct produced in the gas treatment, which-in this case amounted toonly cc., was distilled over below 90 C. The fraction distilled overbetween 102 and 110' C. was a'mixture of ethylene chlorhydrin and water.

The ethylene chlorhydrin solution was hydrolyled with 50 grams soda-ashunder reflux and the free acid neutralised'withsodium hydroxide. 1 I vThe mass was distilled oil under vacuum j salt filtered oi! as i'ormed.About'25 cc. or .semipurified slycolwas obtained.

. 100cc. traction of ethylene chlorhydrin, water sodium chloride wasmixed with methyl alcohol,

and the undissolved salt filtered on, The filtrate which containedalcohol and ethylene glycol was then distilled under reduced pressure toremove the methyl alcohol from the residue of grams of ethylene glycol.

v E's-ample III A 500 .cc. quantity of concentrated. sulphuric acid washeated to C. and ethylene; sulphur dioxide and chlorine were bubbledtherethrough I in the ratio of one volume of ethylene to 1%volumes-'otsulphur dioxide-to one volume of chlorine. The. chlorineandsulphur dioxide were preliminarily mixed and. then introduced-alongwith the ethylene, a'mechanical stirrer was suspended in the acid body.The gastreatment of t'he acldwas continued may, hours and-thetemperature of the acid was maintained at about 50 C. during this time.I

. At the end of the treating time '70 cc. of oily.

product was separated and half 0! the remainder was treated as in theforegoingexample to produce ethylene chlorhydrin and .then ethyleneglycol. About 20 cc. of'the latter was produced. The other half ofv theremainder was treated the same as in the foregoing example except thatthe acid was not heated before dilution.

The glycol product from the second half was about 10% of that producedwith heating before dilution. x

Example IV A 500 cc. quantity of concentrated sulphuricacid wasmaintained at from85 to 95 C. and agitated with a mechanical stirrer;During heating and while agitated ethylenaisulphur dioxide and chlorinewere bubbled into the acid in the proportions of one volume ofethylene'to 1% volumes 0! sulphur dioxide to one volume of chlorine.This treatment was continued about 6% hours. A 300 cc. portion'oi thegas-treated acid was diluted with 500 cc. of water and dis-v A 500 cc..quantity or concentrated sulphuric acid was maintained at from .to C.and. agitated as in the previous-examples. "While agitated'ethylene,-sulphur dioxide and chlorine, were introduced inthe ratio of cc. per'minute to 162' cc.- per minute. 80 cc. per minute' respecover a, periodor 0% The thus then heatedto ciiorf-iliteen under pressure.

' A 250portion'ofthe acid product was dilu with an equal quantity ofwater, refluxed for ten minutes and then distilled to yield the desiredmixture whichhad a specific gravity of 1.05. This was neutralized with96 cc. of 2/l0-nonnal hydroxide'and hydrolyzed with a solution or 25grams soda-ash in 50 cc. of water, which was added over a. period. ofthree hours by means 7 01a dropping funnel. During the hydrolysisthe'mixturewas maintained at a boil under reflux.- The resultant product wasconcentrated under vacuum to remove water and the residue taken up withmethyl alcohol in order'to separate the sodium chloride formed duringneutralization.

The alcohol was distilled oil and 15 cc. of ethylene glycol wasproduced.

Another 250 cc. portion 0! gastreated acld'was similarly treated toproduce the ethylene chlorhydrin solution. but'in thisinstancehydrolysis was accomplished by boiling under reflux with 25 grams orsodium bicarbonate." Theresultant ethylene glycol was'purlfledas'beiore. The yield was 1000.

vlgiulverle V1 A 500 cc. quantity oi ooiicentrated sulphuric acid was,treated' with ethylene, sulphur dioxide and chlorine which were bubbledinto the acid at ,1 the rates or 100 ccfoi' ethylene to 118- cc. :ofsulphur dioxide to 115 cc. oi chlorine per minute.

During the gas treatment the acid-was agitated by stirring, as in theprevious examples, and was maintained at .irom 60C.,to 55 C. and thereaction wascarried out in the presence of actinic light. The treatmentcontinued for .7 hours and I 83 cc. of oily product wias producedandseparated. v V

The gas treated acid was treated as set forth in the foregoing examplesto yield the ethylene chlorhydrin' and ethylene glycol.-

- Example VII "The procedure of the preceding example was repeatedexcept that the reaction-was carried out at C. and in the absence oractinic' light. No oily product-was produced. The treatment yieldedethylene chlorhydrin when treated as set forth in the: :precedingexample, and from the chlorhydrln. glycol was; produced.

. Example VIII As an illustration of the rate oi production oi theintermediate products in the acid mass, 907

grams of concentrated sulphuric acid was treated with ethylene, sulphurdioxide and chlorine in the proportion of one volume of. ethylene to twovolumes of sulphur dioxide to one volume of chlorine. Not all of the gaswas absorbed and the excess was permitted to escape. The acid wastreated in the presence of a 250 watt lamp and the treatment continuedfor 16 hours. The acid was maintained in an agitated condition duringtreatment by using a mechanical stirrer. The temperature of the acid was30' C. at the beginning and rose under the influence of the reaction anddue to the heat emanated by the lamp, to about 52 C. The acid gainedweight according to the following table:

Gain in Hours liter treatment began weight Grams or an average of 7.7grams per hour.

. with sodium hydroxide .and hydrolyzed with sodium bicarbonate to formethylene glycol. The

yield was about 40 cc. of glycol having a specifi -gravity ofapproximately 1.12 at 60 F.

Example, IX As a further example of reaction in acid 347 grams of 90%phosphoric acid were placed in a three neck flask. The flask wasprovided with a mechanical agitator and with a reflux condenser. Actiniclight was supplied by a 250 watt filament lamp and the temperature ofthe reaction flask was controlled by a water bath which was maintainedat 20 0. Into this reaction arrangement gases were introduced asfollows:

propylene 88 cc. per minute,'sulphur dioxide 118 cc. per minute, andchlorine 92 cc. per minute. The reaction was continued for five andone-half hours during which the phosphoric acid gained 181 grams inweight. At the end of the flve and one-half hours the entire reactionmass was transferred to a separating funnel where it separated into twolayers. The bottom .layer consisted of the acid and products of thereaction dissolved or otherwise incorporated therein. The oily top layerof 100 cc. was refluxed for three hours with 100 cc. of water. 70 cc. ofthe oily product remained after refluxing. The oil had a density oi 1.16and boiling point of around 95 C., characteristics of dichlor propane.

The phosphoric acid layer was then heated to 150 C. under 27 inches ofmercury vacuum, durreconcentrated. About 18 cos. of glycerine wereobtained.

Ethylene may be reacted with sulphur dioxide and chlorine in thepresence of sulphuric acid,

in accordance with the foregoing procedures, to produce reactionproducts which are collected in the sulphuric acid. Upon subsequentheating of the acid, containing such products, a decomposition takesplace, liberating hydrochloric acid and sulphurdioxide. A product, vinylchloride, is formed in the sulphuric acid, but is immediately reactedupon by the sulphuric acid to produce the ester which may then behydrolyzed with water to form ethylene chlorhydrin.

Various types of apparatus may be used. Any of the non-corrosivematerials used for'chemical apparatus may be employed. Means fordistributing the gases may include porous diaphragms, perforated coilsor similar devices, which may be used alone or in conjunction withsuitable conventional agitators. Instead of a closed vessel providedwith a reflux condenser, a long narrow tube may be used. The tube ispreferably a vapor phase reaction zone, but it may be partially filledwith a solution of the alkene in a suitable solvent, the chlorine-sulfurdioxide mixture being bubbled through it,- or it may be partially filledwith'the solvent, and a mixture of all these reactants bubbled through.Such reaction tubes can be fllled with various inert materials thatprovide an extensive surface and thus promote reaction between a liquidand a gas, e. g. Raschig rings, broken glass, glass beads, glass rings,platinum gauze, and chains or rings of any inert material. conditionsmay be so chosen that the process will be a batch or continuous one,unreacted ingredients being recovered, purified, and recycled, ifdesired. Recycling, with introduction of additional sulfur dioxide andchlorine as needed, is particularly significant for an economicalprocess and satisfactory over all yield since the yield per pass isusually low.

ing which a total of 8 grams of gases were removed. The acid was thendiluted with an equal proportion of water and distilled. A 100 cc.fraction collected between the boiling points of 102 and 105 C., washydrolyzed with sodium out. The residue was extracted with alcohol andIn any of the foregoing procedures, an alcohol may be substituted forthe corresponding hydrocarbon. Thus, for example, I may use ethylalcohol instead of ethylene or propyl alcohol instead of propylene. Insuch instances the alcohol is dissolved in the acid, for examplesulphuric acid and the mixture thus produced is then treated withsulphur dioxide and chlorine. The remaining steps in the procedure areas described above for the several reactions using the varioushydrocarbons. Similarly, bromine, fluorine, or iodine vapors may besubstituted for the halogen, chlorine, and selenium or tellurium oxidesmay be used instead of sulphur dioxide.

The concentration of sulphuric or phosphoric acid when used may beincreased or decreased as desired although acid of high concentration ispreferable. The residual diluted sulphuric acid which remains afterremoval of the products of this invention may be concentrated andre-used for the formation of further products, in a recyclic procedure.

In several of the examples set forth above the ethylene or propylenechlorhydrin produced has .been illustrated as used in theproduction ofspecifled products; such as ethylene glycol from ethylene chlorhydrin.It is obvious that the chlorhydrinsmay be used for many other purposes.

It will be obvious to those skilled in the art that these and many othermodifications may be made in the details of the foregoing procedureswithout departing from the spirit of the invention.

Apparatus and I claim: 1. An improved method of reacting upon a gaseousolefin which comprises simultaneously introducing said olefin, chlorineand sulphur dioxide into a strong poly-basic mineral acid whilemaintaining the temperature of said ingredients in the range of to 100"C., and thereafter sepa-' rating the thus formed reaction compounds.

2., An improved method of reacting upon a gaseous olefin which comprisessimultaneously in-' troducing said ol fin, chlorine and sulphur dioxideinto sulphuric acid while maintaining the temphuric acid to term an acidreaction mass while maintaining the temperature in the range from 0 to100 0., then heating the acid reaction mass to a more elevatedtemperature, diluting the acid reaction mass' with water, and distillingoi! the thus formed ethylene chlorhydrin.

5. The method of reacting upon propylene which comprises introducingpropylene, chlorine and sulphur dioxide into 'a strong polybasic min-'eral acid to form an acid reaction mass while maintaining thetemperature of said mass from 0 to 100 C., diluting the acid reactionmass and thereafter separating the thus formed reaction product.

6. The method of reacting upon propylene which comprises introducingpropylene, chlorine CERTIFICATE Patent No. 2, 78,101

CORTES and sulphur dioxide into phosphoric acid to form an acid reactionmass while maintaining the temperature of said mass from 0 to C.,heating the mass, diluting the mass with water after heating andthereafter separating the thus formed products.

CORTES F. REED.

or CORRECTTON.

June 12, 19 -5.

F. REED.

It is hereby certified that error appears in the printed specificationof the above numbered patent' requiring correction as follows: Pageh,first i c olumn line 25, in the table, last column thereof; for thenumeral "82" read 87- 11116.24; for 7 read ..12'T--; nd that the saidLetters Patent should be read with this correction therein that the samemay conform to the record of the case in the Patent Office.

S igned (Seal) and sealedthis 16th day of October, A. D. i915.

Leslie Frazer First Assistant Commissioner of Patents.

I claim: 1. An improved method of reacting upon a gaseous olefin whichcomprises simultaneously introducing said olefin, chlorine and sulphurdioxide into a strong poly-basic mineral acid while maintaining thetemperature of said ingredients in the range of to 100" C., andthereafter sepa-' rating the thus formed reaction compounds.

2., An improved method of reacting upon a gaseous olefin which comprisessimultaneously in-' troducing said ol fin, chlorine and sulphur dioxideinto sulphuric acid while maintaining the temphuric acid to term an acidreaction mass while maintaining the temperature in the range from 0 to100 0., then heating the acid reaction mass to a more elevatedtemperature, diluting the acid reaction mass' with water, and distillingoi! the thus formed ethylene chlorhydrin.

5. The method of reacting upon propylene which comprises introducingpropylene, chlorine and sulphur dioxide into 'a strong polybasic min-'eral acid to form an acid reaction mass while maintaining thetemperature of said mass from 0 to 100 C., diluting the acid reactionmass and thereafter separating the thus formed reaction product.

6. The method of reacting upon propylene which comprises introducingpropylene, chlorine CERTIFICATE Patent No. 2, 78,101

CORTES and sulphur dioxide into phosphoric acid to form an acid reactionmass while maintaining the temperature of said mass from 0 to C.,heating the mass, diluting the mass with water after heating andthereafter separating the thus formed products.

CORTES F. REED.

or CORRECTTON.

June 12, 19 -5.

F. REED.

It is hereby certified that error appears in the printed specificationof the above numbered patent' requiring correction as follows: Pageh,first i c olumn line 25, in the table, last column thereof; for thenumeral "82" read 87- 11116.24; for 7 read ..12'T--; nd that the saidLetters Patent should be read with this correction therein that the samemay conform to the record of the case in the Patent Office.

S igned (Seal) and sealedthis 16th day of October, A. D. i915.

Leslie Frazer First Assistant Commissioner of Patents.

